Fire extinguishing method

ABSTRACT

A method of extinguishing fires comprising providing a source of fire retardant flowable material near ground level and in substantial quantities, and conveying the fire retardant material to an airborne distributor for distributing the flowable material. The distributor is supported by an airborne vehicle and the conduit between the source and the distributor is rapidly set up utilizing aerial conveyance of the conduits.

United States Patent 1191 Rainey et al.

[ 1 Sept.- 18, 1973' FIRE EXTINGUISHING METHOD [22] Filed: Aug. 7, 1969[21] Appl. No.: 848,248

521 U.S. (:1. 169/2 R, 169/13, 169/16 51 Int. Cl. A62c 3/00 58 Field 61Search 169/2 R, 2 A, 13, 169/16; 239/171, 195, 197, 198, 199; 244/136[56] References Cited 7 UNITED STATES PATENTS 1 1,523,926 1/1925 Ypma,169/2 1,953,331 4/1934 Armstrong 169/2 2,266,334 12/1941 Rice 239/195 X2,634,165 4/1953 Murphy 244/136 x 2,779,421 1/1957 Rust 169/1 3,273,6519/1966 Andrews... 169/2 X 3,381,922 5/1968 Laing 239/171 X 3,485,30212/1969 Thorpe 169/2 3,372,872 3/1968 Le Bus et al 239 2 FOREIGN PATENTSOR APPLICATIONS OTHER PUBLICATIONS Equipment Development Report No. 44published by U.S. Department of Agriculture, Forest Service Division,and titled Improved Fire Hose Dispensing Tray for Helicopters," byArcadia Equipment Development Center, Arcadia, California, dated Nov.,1956, cover page and pages 8, 9, 1O, 18 and A-3 relied on for rejection.

Primary Examiner-M. Henson Wood, Jr. Assistant Examiner-John J. LoveAttorney-Smyth, Roston & Pavitt 571 ABSTRACT tween the source and thedistributor is rapidly set up utilizing aerial conveyance of theconduits.

8 Claims, 3 Drawing Figures Patented Sept. 18, 1973 3,759,330

FIRE EXTINGUISHING METHOD BACKGROUND OF THE INVENTION Forest fires oftenoccur in remote areas where it is most difficult to obtain access to thefire. ln fire danger areas, the sources of fire retardant material maybe remote from the fire. These factors combine to create a seriouslogistics problem, i.e., how to'get sufficient fire retardant materialto the remotely located fires as quickly as possible. An additionalproblem is finding the most efficient manner of distributing the fireretardant materials at the fire.

In an effort to solve these problems, aircraft have been used to dropbombs or containers filled with fire retardant material. Althoughaircraft can reach relatively inaccessible areas, aircraft are limitedby the weight of the fire retardant material which they can carry. Inaddition, the containers may not break until they strike the ground inwhich event the contents thereof will be of little or no effect inextinguishing a treetop fire.

Another prior art device uses a tank of fire extinguishing materialcarried by an aircraft. The material in the tank can be expelled overthe fire area. This device is limited by the capacity of the tank. Inaddition, the aircraft must return to the source to have the tankrefilled and during this time it cannot exert any retarding effect onthe fire. Thus, both of these prior art procedures are quite inefficientand leave unsolved the basic logistics problem of how to rapidly getmaximum fire retardant material to the fire area.

SUMMARY OF THE INVENTION The present invention solves these problems bysupplying unlimited quantities of fire retardant material to the desiredarea. This can be accomplished by using a source of fire retardantmaterial at ground level and an airborne distributor. The fire retardantmaterial should be flowable so that it can be pumped through a conduitto the aerial distributor for distribution over the desired area.

Because the source is at ground level, the amount of fire retardantmaterial distributed by the distributor is not dependent upon the sizeof tank that the aircraft can carry. Rather, the ground level source mayprovide an unlimited or endless supply and may be, for example, a lake,river, well, fire hydrant, etc. Of course, limited quantity sources suchas tanks of water or fire retardant chemicals can also be used. Wherelimited quantity sources are used, the present invention still offers asubstantial advantage in that the airborne distributor can remain aloftwhile a ground crew rapidly makes the necessary conduit connections to anew unreplenished limited source.

The distributor is preferably carried by an airborne vehicle such as arotary wing aircraft. The distributor may be mounted on the aircraft orsuspended beneath the aircraft. Alternatively, the distributor may besupported on the ground or elsewhere while it is discharging fireretardant material and it may be moved or indexed between stations withan airborne vehicle. Preferably, the distributor is suspended beneaththe aircraft to permit the helicopter and its occupants to be as remoteas possible from the fire area while permitting the distributor to berelatively close to the fire area to minimize evaporation and drift ofthe fire retardant materials. This form of aerial distribution permitsthe fire retardant materials to function at treetop level as well asground level and also permits controlling of the distributor movementsfrom the airborne vehicle.

The helicopter moves the distributor over the desired area at thedesired rate of speed. The distributor may direct the fire retardantmaterial directly on the fire or be used to form a water break at alocation spaced from the fire front. Preferably a flexible connector isused to connect the distributor to the conduit which leads to the groundsource.

Not infrequently the source of fire retardant materials may be quiteremote from the fire. The present invention solves this problem byproviding for the aerial conveyance of long flexible conduits from theremote source to a region adjacent to the fire. Specifically, one end ofa first conduit section is suitably connected to a source of fireretardant material and the other end of the conduit section is carriedby helicopter for a distance approximately equal to the length of thatconduit. A second conduit is then connected to the first conduit and thesecond conduit is similarly carried by helicopter for a distanceapproximately equal to the length of the second conduit section. Thelast conduit section is connected to the distributor. In this manner,the supply conduit can be rapidly established between a substantialsource of fire retardant material and the distributor. Of course, morethan one distributor may be employed for each supply line and multiplesupply lines may be used, if desired.

The conduit sections should be flexible to facilitate aerial movementthereof. The conduit sections should also be collapsible so that theywill require minimum storage space within the aircraft.

Pumps can also be supplied by helicopter as needed along the supplyconduit. Preferably the pumps are located between adjacent conduitsections. The pumps may be modular units which can be left at theirrespective stations by the helicopter carrying same. Alternatively, thehelicopter may carry a pump which can be powered by the rotary wingpower source or an auxil- I iary power source, in which event thehelicopter, after having laid its length of conduit section remains onthe ground to serve as a pumping station.

The pumping stations can be located at ground level. Alternatively, oneor more of the pumping stations can be airborne in which event, they arepreferably carried by a helicopter. One advantage of making at least thepumping station that is farthest downstream an airbornestation is thatthe airborne distributor is afforded greater maneuverability.

irregularities in ground contour and foliage ma cause kinks in theflexible conduit laid by helicopter. Such kinks would subtantiallyimpede the flow of water through the conduit and may give rise todisruptive forces when such kink is initially contacted by the wa ter.To obviate this problem, the present invention provides for charging ofthe conduit section with a fluid such as air to straighten the conduitsection prior to connecting the conduit section to an adjacent conduitsection.

The invention, both as to its organization and method of operationtogether with further features and advantages thereof may best beunderstood by reference to the following description taken in connectionwith the accompanying illustrative drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary, schematic,side elevational view of a fire fighting system constructed inaccordance with the teachings of this invention and carrying out themethod of this invention.

FIG. 2 is a fragmentary, schematic, side elevational view illustrating apreferred manner for aerially laying of the supply conduit.

FIG. 3 is a fragmentary, schematic, side elevational view showing analternate system and method of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawing and inparticular to FIG. 1 thereof, reference numeral 11 designates a fireextinguishing system adapted for carrying out the method of thisinvention. In the embodiment illustrated, the system 11 includes a pump13 and syphon 15 located at ground level near a source of fire retardantmaterial in the form of a lake 17. One end of thesyphon 15 is submergedin the lake 17 and a strainer 19 prevents debris and other solidmaterial from entering the syphon.

Virtually any source flowable fire retardant material can be utilized.Normally fixed sources such as lakes, hydrants, rivers, and wells arepreferred because they can provide a virtually unlimited or endlesssupply of water. However, it will be appreciated that tanks of chemicalsand other fire retardant materials whether fixed or vehicle mounted canalso be utilized.

The pump 13 and the syphon 15 can be flown to the lake 17 by ahelicopter or other suitable airborne vehicle and rapidly set up. Thepump 13 in the embodiment illustrated is a modular unit of substantialcapacity having its own power supply; however, the pump 13 can bepermanently mounted to a helicopter and be driven by a power take-offshaft from the main power source of the helicopter. l

A conduit section 21 interconnects the pump 13 to a pump 23 mounted on ahelicopter 25. The conduit section '21 is preferably in the form of along flexible hose of substantial internal diameter so that a largevol-' ume of water can be readily pumped therethrough. Although thelength of the conduit section 21 may vary, it is contemplated that theconduit section will be of substantial length and may be, by way ofexample, l,000 feet long.

In the'embodiment illustrated, the pump 23 and helicopter 25 are locatedat ground level. The pump 23 is mounted on the helicopter 25 and isdriven on a power take-off shaft from the main helicopter power sourcewhich might be a turbine. This requires that the helicopter remain withthe pump 23 but facilitates rapid movement of the pump. Alternatively,the pump 23 may have its own power supply. If desired, the pump 23 maybe a separate modular unit such as the pump 13 in which event, thehelicopter 25, after the pump 23 has been installed, may leave thepump23 at ground level and fly to a new location.

A conduit section 27, which may be identical to the conduit section 21,connects a pump 29 mounted on a helicopter 31 to the pump 23. Thehelicopter 31, like the helicopter 25 is at ground level. The pump 29and the helicopter 31 may be identical to the pump 23 and helicopter 25,respectively. Alternatively, the pump 29 may be a modular unit like thepump 13 in which event the helicopter 31, after installation of thepump, may move to a new location.

A distributor in the form of a deluge rig 33 is supported above groundlevel by an airborne vehicle such as a helicopter 35. Although thedeluge rig 33 may be of various designs, in the embodiment illustrated,it includes a frame 37 and three spray heads 39, each of which includesone or more orifices for directing the water laterially and/ordownwardly of the spray head. Preferably the spray heads 39 are spacedlaterally and the spray pattern is so selected that a relatively largearea can be covered by the deluge rig 33.

The deluge rig 33 may be mounted directly on the helicopter 35 ifdesired. .However, it is preferred to suspe'nd the deluge rig 33 withone or more cables 41 from the helicopter 35.

The deluge rig 33 is connected to the pump 29 by a third conduit section43 which may be identical to the conduit section 21. A flexible coupling45 is utilized to connect the conduit section 43 to the deluge rig 33.With the deluge rig 33 suspended from the helicopter 35, the amount offluid andthe direction in which such fluid is discharged from each ofthe spray heads 39 should be substantially balanced so that the netreaction force on the deluge rig is minimized.

With the system 11. set up as shown in FIG. 1, the pumps 13, 23 and 29are started so that water is drawn from' the lake l7 and pumped in hugequantities through the conduit sections 21, 27 and 43 to the deluge rig33. The deluge rig, which is suspended perhaps several hundred feetabove ground level, disperses the water through the spray heads 39. Thehelicopter 35 moves at a prescribed rate so that the deluge rig cancover a substantial area or the helicopter may index the rig 33 betweenstations with the latter being substantially stationary at each of thestations. The deluge rig 33 may be used to provide a fire break or todistribute water directly on the burning area. I

Of course, more than one deluge rig 33 may be connected to the outlet ofthe pump 29 and one or more of the systems 11 may be employedsimultaneously. The number and size of the pumps utilized willbedetermined by the distance which the water must be pumped, the quantityof water desired, and the amount that the water must be elevated betweenthe lake 17 and the deluge rig 33. .Of course, if the water source isitself pressurized as when a hydrant source is utilized, no pumps may benecessary. In addition, if the elevation of the lakel7 were above theelevation of the deluge rig 13 when the latter was in flight, thepumping requirements would be significantly reduced.

FIG. 2 diagrammatically illustrates a preferred manner of setting up andinstalling the system 11. First, the pump 13 and-the syphon 15 are movedto the lake 17 via helicopter and properly set up at ground level. Next,the helicopter 25 while aloft may drop one end of the conduit section 21for connection to the distion 21 with 'air may be accomplished in anysuitable manner such as with an air pump or with the bleed air from theturbine which is the main power source for the helicopter 25. Thedownstream end of the conduit section 21 is then connected to the inletof the pump 23.

Next, the helicopter 31 drops the upstream end of the conduit section 27adjacent the helicopter 25 for attachment to the discharge side of thepump 23 which connection can be made by the crew in the helicopter 25.The helicopter 31 then repeats the procedure described hereinabove withreference to the helicopter 25. If the pump 23 is a separate modularunit, the helicopter 25 need not remain in position as shown in FIG. 1.

The conduit section 43 can be connected to the pump 29 and to the delugerig 33 with the latter resting at ground level. The helicopter 35 thenraises the del' uge rig 33 aloft as shown in FIG. 1. A means of controlsuch as a manually or automatically controlled valve 47 near thedischarge end of the pump 29 can be utilized to control the flow ofwater to the deluge rig 33. Of

out. This requires that the flexible conduit section 27a extend aboveground level between the pumps 23a and 29a and that the conduit 27a beconnected to the pump 290 by a flexible coupling 49. Similarly, theflexible conduit section 43a is connected to the discharge side of thepump 29a by a flexible coupling 51. In all other respects, the systemshown in FIG. 3 is identical to the system shown in FIG. 1 and themethods carried out by these two systems are also identical except tothe extent,

expressly indicated herein. A primary advantage of the method of FIG. 3is that the deluge rig 33 may be moved through a larger area aspermitted by conduit sections 27a and 43a.

Although exemplary embodiments of the invention have been shown anddescribed, many changes, modifications, and substitutions may be made byone having ordinary skill in the art without necessarily departing fromthe spirit and scope of this invention. We claim: l. A method for therapid aerial distribution of a flowable material for retarding a firecomprising:

providing a source'of the flowable material substantially at groundlevel, said flowable material having fire retardant characteristics;positioning one end of a first conduit section adjacent and incommunication with the source of flowable material; conveying the otherend of the first conduit section to a firststation remote from saidsource of flowable material utilizing an airborne vehicle with said stepof conveying being at least partially carried out with said airbornevehicle aloft;

interconnecting said other end of said first conduit section to one endof a second conduit section;

conveying the other end of the second conduit section to a secondstation remote from said first station utilizing an airborne vehiclewith said last mentioned step of conveying being at least partiallycarried out with said airborne vehicle aloft;

flying an airborne vehicle over the region at which the flowablematerial is to be distributed;

interconnecting a third conduit section to a distributor and the otherend of said second conduit section;

supporting the distributor on said last mentioned airborne vehicle sothat the distributor is above ground level at said region;

pumping the flowable material from said source through said conduitsections andv through said distributor to thereby distribute theflowable material over said region; and

charging said first conduit section with air to at least substantiallyeliminate any kinks therein prior to interconnecting said first andsecond conduit sections.

2. A method as defined in claim 1 wherein said first and second stationsare at ground level.

3. A method as defined in claim 1 wherein said second station iselevated above ground level by the airborne vehicle utilized in theconveying of said second conduit section whereby the distributor hasincreased freedom of movement.

4. A method as defined in claim 1 wherein said first and second conduitsections are conveyed by first and second airborne vehicles,respectively, and said steps of conveying said first and second conduitsections includes landing said first and second airborne vehicles,respectively, at said first and second stations, respectively, each ofsaid first and second airborne vehicles carrying pumpsand said step ofpumping including operating said pumps carried by said first and secondairborne vehicles to 'pump the flowable material through said conduitsections. 3 I

5. A method as defined in claim 1 including interposing pumps betweensaid first and second conduit sections and between said second and thirdconduit sections and said step of pumping includes operating said pumpsto force the flowable material through said -conduit sections. I

6. A method as defined in claim I wherein said region is close to saidfire, said last mentioned airborne vehicle is a rotary wing aircraft,and said step of supporting includes suspending the' distributor from arotary wing aircraft so that the distributor is relatively close to saidregion and saidaircraft is relatively remote from the fire.

. 7. A method as defined in claim 1 including flexibly interconnectingthe third conduit section to the distrib-,

utor.

8. A method as defined in claim I wherein said flowable material iswater and said source is virtually unlimited, said step of pumping beingcarried out substantially continuously.

1. A method for the rapid aerial distribution of a flowable material forretarding a fire comprising: providing a source of the flowable materialsubstantially at ground level, said flowable material having fireretardant characteristics; positioning one end of a first conduitsection adjacent and in communication with the source of flowablematerial; conveying the other end of the first conduit section to afirst station remote from said source of flowable material utilizing anairborne vehicle with said step of conveying being at least partiallycarried out with said airborne vehicle aloft; interconnecting said otherend of said first conduit section to one end of a second conduitsection; conveying the other end of the second conduit section to asecond station remote from said first station utilizing an airbornevehicle with said last mentioned step of conveying being at leastpartially carried out with said airborne vehicle aloft; flying anairborne vehicle over the region at which the flowable material is to bedistributed; interconnecting a third conduit section to a distributorand the other end of said second conduit section; supporting thedistributor on said last mentioned airborne vehicle so that thedistributor is above ground level at said region; pumping the flowablematerial from said source through said conduit sections and through saiddistributor to thereby distribute the flowable material over saidregion; and charging said first conduit section with air to at leastsubstantially eliminate any kinks therein prior to interconnecting saidfirst and second conduit sections.
 2. A method as defined in claim 1wherein said first and second stations are at ground level.
 3. A methodas defined in claim 1 wherein said second station is elevated aboveground level by the airborne vehicle utilized in the conveying of saidsecond conduit section whereby the distributor has increased freedom ofmovement.
 4. A method as defined in claim 1 wherein said first andsecond conduit sections are conveyed by first and second airbornevehicles, respectively, and said steps of conveying said first andsecond conduit sections includes landing said first and second airbornevehicles, respectively, at said first and second stations, respectively,each of said first and second airborne Vehicles carrying pumps and saidstep of pumping including operating said pumps carried by said first andsecond airborne vehicles to pump the flowable material through saidconduit sections.
 5. A method as defined in claim 1 includinginterposing pumps between said first and second conduit sections andbetween said second and third conduit sections and said step of pumpingincludes operating said pumps to force the flowable material throughsaid conduit sections.
 6. A method as defined in claim 1 wherein saidregion is close to said fire, said last mentioned airborne vehicle is arotary wing aircraft, and said step of supporting includes suspendingthe distributor from a rotary wing aircraft so that the distributor isrelatively close to said region and said aircraft is relatively remotefrom the fire.
 7. A method as defined in claim 1 including flexiblyinterconnecting the third conduit section to the distributor.
 8. Amethod as defined in claim 1 wherein said flowable material is water andsaid source is virtually unlimited, said step of pumping being carriedout substantially continuously.